A Man Standing On A road has to hold his umbrella at 30 deg with the vertical to keep the rain away he throws the umbrella and starts running at 10 km/hr then he finds that raindrop are hitting his head vertically than speed of raindrop wrt moving man is?

1 Answer
Mar 11, 2018

#10 sqrt(3) Km# # hr^-1#

Explanation:

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See we have constructed this vector diagram,where #V_r# is the velocity of rain,#V_m# is the velocity of man, and #V_(rm)# is the velocity of rain w.r.t man.

So,using Lami's theorem,

#(V_m)/ sin 30 = (V_(rm))/sin 60#

so,#(V_(rm))=V_m sin 60/sin 30=10*sqrt(3)=17.31 (Km)/(hr)#